A generic, and sometimes humorous, reply to someone who took way too much time describing something, while the description would've been sufficiently clear and complete with less words. The term is both used by impatient kids when they can't concentrate long enough to read more then two sentences, and the more intelligent generation-X poster when the "long post" in question could've been described just as well, but much shorter, this comment can be taken either way.

Also a reply to long, attention-whorey spam topics.

Politically Involved Chap: (long rant about the state of affairs in the presidential houses of middle-west Europe)
Nooblet455: OMG TOO LOGN DIDNT READ!1